1. Field of the Invention
The present invention relates to an apparatus for generating high-pressure steam that is essential in industrial fields, and more particularly, to an apparatus and method for generating more efficiently and economically high temperature steam used in industrial fields.
2. Description of the Related Art
In order to obtain steam of high temperature and pressure in industrial fields, industrial water is generally heated in a boiler at high temperature and pressure to generate the steam of high temperature and pressure. It has been found that steam ordinarily obtained by means of such a conventional method has a temperature of about 140° C. and is maintained at a pressure of about 12 kgf/cm2, whereas better-quality steam required depending on industrial fields has a temperature of about 180° C. and is maintained at a pressure of about 15 kgf/cm2.
Such a conventional method for generating steam employs a phenomenon by which water in a liquid phase is vaporized into gaseous water vapor through phase change at about 100° C. under the atmospheric pressure and the temperature of the gaseous water vapor is raised due to an increase in the internal energy of the gaseous water vapor under high pressure.
However, when water in a liquid phase is heated in a conventional boiler in such a conventional method, a large amount of heat should be applied to the water so as to vaporize the water in the boiler. This means that the entire water contained in the boiler should be heated to be vaporized and resulting water vapor should be further heated to a desired temperature in order to generate steam. Therefore, the conventional method for generating steam has disadvantages in that an excessive amount of energy should be input and the amount of generated steam is small as compared to the amount of input energy.
Moreover, although a large amount of energy is supplied to the boiler in the conventional method, most of the supplied energy continuously vaporizes water contained in the boiler to generate water vapor and it is not possible to further raise the temperature of the generated water vapor. Thus, there are disadvantages in that the temperature of the generated water vapor is limited (e.g., to 180° C.) and it is not possible to obtain water vapor of a high temperature greater than 180° C.
In addition, the conventional method for generating steam has a disadvantage in that a large-sized boiler should be equipped to generate water vapor, resulting in increased investment costs.
Furthermore, according to the conventional method for generating steam, in view of safety, facilities such as a boiler that actually generate water vapor are installed at locations far away from places where the water vapor are to be actually used. Thus, a lot of utility facilities including pipe lines are required to carry the generated water vapor to the places where the water vapor is to be actually used. Therefore, the conventional method for generating steam has problems in that high maintenance costs in addition to the high investment costs are required, leading to increase of steam generation costs.
As described above, a conventional method for generating steam has inherent problems in that a small amount of steam is generated for input energy, a greater amount of energy is required when steam with a temperature higher than a typical temperature is needed, and it is not possible to obtain steam with an ultra-high temperature of 200° C. or more.